IT IS NUMBER #4!!!!
Well, being part of this community for awhile, SPI finally decided to crap out on me at 130k. I decided to put my mechanical skills to the test and try to rebuild it and hopefully succeed as some of us have with their rebuilts. Since I am from Canada and Headsonly doesn't ship here and to avoid a headache in case anything goes wrong, I am going with my local machine shop. Also, it is much harder to source parts here because swapping engines is the way to go around here without giving them a second chance at life.
So far, I have taken everything apart to find piston #4 chewed up. Cylinder walls look good without any scratches. Cleaned out my intake and found a few peaces there as well as on top of the cylinder.
HUGE THANK YOU goes to WrenchTurnerDave
for helping me out a lot so far with all the questions I have. Also thanks to iminhell
for answering my question regarding the injector pintle cap.
Here are some of the pics.